TORONTO --The Toronto Maple Leafs and the Washington Capitals have been working extra time in their first-round Eastern Conference playoff series.

The first three games have all gone to overtime and, for the second game in a row, the young, upstart Maple Leafs came out on top.

Tyler Bozak deflected a shot by Nazem Kadri at 1:37 of overtime Monday night and the Maple Leafs defeated the Capitals 4-3 to take a 2-1 lead in the best-of-seven series.

"We had fresh ice on a power play, there wasn't much more you could ask for at the start of a period," Bozak said. "(Kadri) made a great play to me and I just tipped it and I'm lucky it went in."

The goal came with Washington's Lars Eller serving a high-sticking penalty assessed at 19:44 of the third period.

The Maple Leafs twice overcame two-goal disadvantages and were down by two fewer than five minutes into the game. They never led until Bozak's goal in a mistake-filled game by both teams.

"We were terrible with our defensive reads all night," Maple Leafs coach Mike Babcock said. "We had lots of energy tonight, let's just say that. I thought today for whatever reason we were amped up to say the least. We had tons of energy. Energy wasn't a problem."

The Capitals had the best record in the Eastern Conference and the Maple Leafs qualified for the playoffs as the second wild card.

"I thought we came out great," Capitals coach Barry Trotz said, "In the first 14 minutes, I thought we had them on their heels, I liked our first period."

Game 4 will be played Wednesday night at the Air Canada Centre

Auston Matthews, Kadri and William Nylander also scored for the Maple Leafs. Matthews and Kadri added assists and Morgan Rielly contributed two assists for the Maple Leafs.

"They're capitalizing on their moments, we're not," Trotz said.

Nicklas Backstrom, Alex Ovechkin and Evgeny Kuznetsov scored for the Capitals. Backstrom also had an assist, and T.J. Oshie recorded two assists.

Frederik Andersen made 23 saves in the Toronto goal. Capitals goaltender Braden Holtby made 24 stops.

"The first half was pretty good," Holtby said. "They had a lucky bounce on the second goal and we kind of got crossed up on the third one. It seems like we didn't push through as well as we can. The rest of the game we didn't push enough. That's a frustrating one. We're going to at the first half and see what we did well and play the full 60 (minutes)."

Backstrom's second goal of the playoffs came while unchecked on a pass from defenseman Nate Schmidt at 2:43 of the first period with the team playing with four skaters each after coincidental minors.

At 4:49, Ovechkin made it 2-0 when he hammered a shot from the high slot for his second goal of the playoffs on a setup from Backstrom.

Matthews knocked in his own rebound for his first playoff goal at 14:08 of the first period to pull Toronto within 2-1.

At 5:39 of the second period, Kuznetsov scored from a sharp angle on a rebound to restore Washington's two-goal margin.

The Capitals failed to take advantage of a five-on-three advantage for two minutes that started at 6:52.

"It's a big moment in the game," Babcock said. "The game is over if they score. That was a huge kill for us."

When the penalties expired, Toronto's Mitch Marner had a chance for a breakaway on a long clearing pass, but Holtby just beat him to the puck and knocked it away.

"There was a chance to take control of the game and we didn't," Trotz said. "Then we had another power-play opportunity and we didn't (score) and then they got some momentum."

Kadri's first goal of the playoffs found its way through at 15:13 of the second period to cut the lead to one.

Nylander scored his first goal of the playoffs at 19:20 of the second on his own rebound to tie the score.

"In the last minute, we can't give up a goal," Trotz said. "They got some momentum."

The Maple Leafs also picked up some steam after a couple of big hits by Kadri in the first period.

"That was a huge turning point," Rielly said. "A huge shift from (Kadri). He's been doing that all year. Not just one shift for him tonight, he was outstanding all night."

NOTES: Toronto D Nikita Zaitsev (upper body injury) returned to the lineup for the first time in the playoffs Monday, taking the place of D Roman Polak (lower body), who is out for the rest of the season after being injured in Game 2. .... The Maple Leafs scored the first goal in each of the first two games of the series. ... The Maple Leafs hosted their first home playoff game since May 12, 2013, when they defeated the Boston Bruins 2-1.